This is a 371 of PCT/EP00/10739 filed Nov. 1, 2000 (international filing date).
This invention relates to a device for filling flowable to pasty filling into tubular packaging material which by means of the filling pressure in the packaging material unilaterally closed at its downstream end is withdrawn. from a filling tube against the frictional force of a brake ring (casing brake) which encloses the filling tube and is held in a housing, a closing means with elements radially crimping the packaging material being disposed subsequent to the filling tube in flow direction of the filling.
There is known a wide variety of such filling devices, for instance for producing sausages. They are usually adapted for the continuous operation for producing a sequence of discrete packages (sausages), the closing means alwaysxe2x80x94intermittentlyxe2x80x94being put into operation when the desired degree of filling of a package has been reached and filling the next package should be started (DE 26 01 595 B2, DE 24 20 202 C2).
In the course of the development, the degree of automation and the operating speed of such filling plants have increased to such an extent that especially the closing means with its crimping elements gathering the packaging material to form a neck (but also the possibly provided separating means) represents a serious risk for the operators, should they try, for instance, to repair a malfunction with the machine running or when the same is slowing down. The same is true when, in the course of the regular operation, the supply of packaging material provided on the filling tube is used up and must be replenished. Therefore, safety regulations provide that extensive covers in the form of grids or the like in flow direction of the filling both before and behind the closing means prevent the access to the same during operation and allow such access only during the standstill of the machine.
In the prior art it is therefore required that when the filling tube must be fitted with new packaging material (usually by swivelling the filling tube to the side), not only the cover on the side of the filling tube is opened, but the entire machine head with the crimping and closing mechanism as well as possibly the separating means and the casing brake together with its housing are moved to the side to such an extent that the filling tube gets clear of these means. This necessitates a complex machine construction and requires considerable operating time.
This should be overcome by means of the invention. The invention provides that the brake ring housing is connected with a coaxially arranged safety ring and can be moved together with the same in axial direction of the filling tube such that the safety ring is located in the active planes of the elements of the closing means when the brake ring has left the filling tube. To clear the filling tube for being newly charged with packaging material, the brake ring housing together with the safety ring need therefore only be shifted in axial direction. When the brake ring leaves its functional position on the filling tube, said safety ring blocks the crimping and clip-setting elements as well as possibly the separating elements which are disposed coaxially with respect to the filling tube and during operation move in radially inward direction. Injuries due to an unintended actuation of these elements are therefore excluded. When the combination of brake ring, housing thereof and safety ring (at the end of charging the filling tube with packaging material) returns from that operating position of the safety ring to its neutral positionxe2x80x94which corresponds to the functional position of the brake ringxe2x80x94, the operability of the crimping and closing mechanism is restored on the one hand, and on the other hand the safety ring now disposed before that mechanism on the filling tube side prevents inadvertent operation of the same, so that there is not required any further cover on the side of the filling tube.
Preferably, the arrangement is made such that at its end facing the filling tube the safety ring is closed by a circular bottom. Due to this design as xe2x80x9csafety bellxe2x80x9d, the stability of the construction is increased on the one hand, and on the other hand its safety function is increased. Furthermore, the brake ring housing can replaceably be arranged at this bottom in a holder attached thereto.
Advantageously, the safety ring (with the brake ring housing) is slidably guided on a longitudinal guideway arranged in parallel to the filling tube and can be moved into its end positions by means of a fluid-actuated cylinder. There may furthermore be provided a safety switch, which switches off the closing means when the safety ring leaves its neutral position, and which initiates a single closing operation when the safety ring returns to its neutral position. The latter leads to the fact that the required closing of the packaging material at the downstream end is effected automatically before the again first filling operation. Then, the usual automatic filling operation can be initiatedxe2x80x94expediently by means of a two-hand operation.
The drawing illustrates the invention with reference to an embodiment, in which:
FIG. 1 shows a top view of the orifice end of the filling tube of the inventive filling device with a closing means and a part of the transport means for the filled packages;
FIG. 2 shows a top view corresponding to FIG. 1, but with the brake ring withdrawn from the filling tube and with the filling tube cleared for being charged with packaging material; and
FIG. 3 shows a side view of segments of the representation shown in FIG. 1.